1. Field of the Invention
The present invention relates to methods for manufacturing press molded articles. More particularly, the present invention relates to methods for manufacturing a press molded article that comprises a substrate layer and a foamed layer, such as a profiled vehicle door trim or a profiled vehicle roof trim.
2. Description of the Related Art
Generally speaking, known profiled vehicle trim products include a profiled plate-like resin substrate layer, a soft foamed layer disposed on the substrate layer, and an uppermost skin or covering layer having embossed patterns formed thereon. Typically, such a trim product is a manufactured as a press molded article by press molding. For example, according to known techniques, an embossed skin material is first adhered to a sheet of foamed material, to thereby form a decorative laminate. Thereafter, a substrate material and the decorative laminate are placed in a press die of a press molding apparatus, and the substrate material is press molded together with the decorative laminate. As a result, the profiled trim product is formed such that the skin layer and the foamed layer are attached to the profiled substrate layer.
However, according to this known method for manufacturing trim products, the foamed layer may be excessively compressed or thinned by the heat and pressure applied during the press molding step. Such a thinned foamed layer may lack elasticity and the foamed layer of the trim product may feel hard. In addition, if the foamed layer is relatively thick, undesirable depressed portions or recesses may be formed in the foamed layer during the press molding step. Such depressed portions may degrade the appearance of the trim product.
Further, because the substrate material is press molded together with a compressible foamed layer in the known technique, the substrate material cannot be desirably or sufficiently shaped or profiled during the press molding step. Such insufficient shaping or profiling of the substrate material may result in a trim product having a dull profile. In addition, the embossed patterns that are previously formed on the skin layer may be deformed or destroyed during the press molding step.
Known trim products have also been manufactured by another method. For example, the embossed skin layer may be adhered to the foamed layer, to thereby form the decorative laminate. Separately, only the substrate material is press molded, to thereby form a profiled or shaped substrate layer. Thereafter, the decorative laminate is adhered to the profiled substrate layer, to thereby form the trim product in which the skin layer and the foamed layer are attached to the profiled substrate layer.
However, this known technique typically increases the minimum number of steps for manufacturing the trim product. In addition, it is generally difficult to adhere the decorative laminate to the shaped or profiled substrate layer. Therefore, labor-intensive and time consuming work is required to form the press molded article using this known method.